E1M9: Operations (Double Impact)

E1M9: Operations is the ninth and secret map of Double Impact. It was designed by Matt Cibulas (RottKing) and Ralph Vickers (Ralphis), and uses the music track "The Demons from Adrian's Pen" by Robert Prince. The par time defined in the DMAPINFO lump of the edition released as official add-on is 19:45.

Essentials
Take the shotgun next to the imp in front of you if needed, then go through the east doorway to dispose of imps and zombies next to a door. Open the door to reach a curved walkway with more of the same enemies as well as a cacodemon, then head east through another door to see two sets of steps that lead down to an area with three metal pillars and a rocket launcher. Between the steps is an alcove with one or two shotgun guys and a switch; flipping the switch will lower the pillars and allow you to get the yellow keycard, but will also allow a variety of enemies to teleport in to the area. With the yellow key, head back to the starting point (the doors you passed through earlier require that key to re-open them) and go through the west doorway this time to a room with two locked doors, then head towards the staircase in the north-west corner; the north wall will open to reveal zombies as you approach it.

Head down the stairs and follow the corridor to a junction, then go through the low doorway on your right to see zombiemen guarding a yellow key door. Open the door and kill the enemies on your right before pressing the button ahead, then go back through the door and head north to see a small doorway leading to an enclosed chamber; the button you just pressed opened this doorway, but ignore it for now and continue north until you see some steps on your right leading up. Go up the steps to find a recessed switch and flip, kill the demons (and spectres on Hurt Me Plenty (HMP) skill level or higher), then go into the chamber and arm yourself before step on the teleporter that has lowered; you will be sent to the west side of the map and will be surrounded by several enemies. Fight your way to the lifts in the south-east corner and activate either one, then go up and continue south-east to a round junction with a tech pillar. Open the north door and follow the corridor behind it to a switch next to a light column, flip it to open a door behind you and release some zombies then go through and follow the hallway to the blue keycard.

Press the button inside the alcove next to open the wall, go down the steps behind it then open the blue key door on your left to return to the starting area. Go back to where you found the yellow key; when you reach the steps leading down to that area, look north to see another blue key door and open it to enter a blue-floored room. There are two hallways on the east side of the room - enter the north hallway with the chaingun and follow it into a larger room, then head west to a door and kill the imps that are released behind you before opening it. The next room contains a nukage pit surrounded by a catwalk - carefully make your way anti-clockwise around the walkway to the room on its south side to find a button, which will open three closets containing cacodemons, demons and imps. Fight your way to the north closet and flip the switch inside it to lower a platform with imps, lost souls and the red keycard.

Go back to the room west of the starting point that had two locked doors, open the south door now then head across a bridge to another smaller door. Open this door and immediately turn left to pass through a metal archway, head through the next room then turn right and right again to see a circular gray tower with an armor inside it. Head down the steps next to the tower and proceed west through a tech corridor, then turn left to see a switch in front of you; pull it then head back through the tech corridor that your way back is blocked by fiery bars and a closet containing several enemies has opened on your right. Press the eye switch on the west wall of this alcove to lower the bars, head back to the small door then run south and west to see that a hallway has opened ahead; go through that hallway to find a medikit, which will cause the wall ahead to lower and reveal a blood pool with one or two cacodemons (they may teleport behind you). Press the metal pillar behind the cacodemons to reveal one or two imps protecting the exit teleporter.

Secrets

 * 1) Inside the blue-floored room with techno pillars at the north end of the map, go to the right wall and press on the recessed terminal to find a chainsaw. (sector 644)
 * 2) South of secret #1, before the collapsing hallway, is an alcove with brown and blue walls. Press on the southern-most blue square in this alcove to open a door leading to a medikit, a rocket and an armor. (sector 189)
 * 3) At the western-most section of the map with the nukage, take either of the two lifts up to the next level, then go north to where the armor bonuses are. A section of the north wall here is misaligned - open it to find health bonuses and a radiation shielding suit. (sector 287)
 * 4) With the radiation suit from secret #3, take the nearby lifts back down and drop into the nukage around the teleport destination. Press the recessed part of the west wall to open it and find a megaarmor. The lift here counts as a secret, taking you to clips, a backpack and a medikit. (sector 268)
 * 5) A wall in the north-east corner of the blue key room has an extra line on it. Open this wall to find armor bonuses, partial invisibility, rockets and stimpacks. (sector 527)
 * 6) After getting the blue key, return to the teleporter that leads to the western-most area and carefully walk around its east side (the west side is too narrow for you to pass through) to find a button on the pillar behind it. This button opens a wall near the yellow key door, and a blue key door is behind that wall. This alternative door takes you to a hidden section where you can get an invulnerability and secret #7 among other things. (sector 143)
 * 7) In secret #6, ride the lift on the north side up to a brown room, then go north-west. At the dead end you see, a button is hidden behind the green pillar with the beating heart. Press this switch to open the door behind you, leading to a room with an armor, a chaingun, a berserk pack and two rockets. (sector 619) This room also contains one to three enemies depending on skill level.
 * 8) When you take the blue door leading into the blue-floored region at the north-eastern part of the map, take the south path. This path dead-ends at a gray wall, but you can lower the section with green staining as a lift to reach a backpack and a medikit (there will also be an imp up here on HMP or higher). (sector 534)
 * 9) Once you pass through the red key door near the starting point you will be on a bridge. Drop into the east ditch and find a hidden switch next to the lift leading back up. Then drop into the west ditch and pass through the open door leading to an alternate section of this area, which will lead you to a supercharge. (sector 313)

Bugs
A floor gives away to reveal a room submerged in blood but also causes a light (thing 117) to snap out of the blood unless the map is played on a Boom-compatible port.

A descending lift with monsters near the end (sector 322) neighbors a ledge that monsters can walk onto and get stuck on, making them unable to attack, when the lift continues down without them.

The final exit-opening switch is separated from the exit by a sludge pit, with a detour connecting the two. When this switch is approached, bars rise to block the route back to the exit, requiring some fighting to lower. If the player raises the bars, neglects the switch, and instead jumps into the sludge pit to take a convenient elevator to the exit, the bars now prevent the player from reaching the exit-opening switch. This can be worked around by using SR50 or a rocket jump straight over the pit.

Current records
The records for the map at the Doom Speed Demo Archive are:

The data was last verified in its entirety on December 9, 2021.

Player spawns
This level contains sixteen spawn points:
 * 1) facing south. (thing 951)
 * 2) facing east. (thing 952)
 * 3) facing north-west. (thing 953)
 * 4) facing north-east. (thing 954)
 * 5) facing south. (thing 955)
 * 6) facing south. (thing 956)
 * 7) facing west. (thing 957)
 * 8) facing east. (thing 958)
 * 9) facing south. (thing 959)
 * 10) facing east. (thing 960)
 * 11) facing west. (thing 961)
 * 12) facing north. (thing 962)
 * 13) facing north. (thing 963)
 * 14) facing south-west. (thing 964)
 * 15) facing north-east. (thing 965)
 * 16) facing north-west. (thing 966)

Things
This level contains the following numbers of things per skill level: